Drug interactions
clozapine + smoking cessation (bupropion/varenicline)
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Overview
Clozapine levels may ↑ when smoking stops (CYP1A2 change).
Mechanism of action
↓ PAH induction of CYP1A2.
Clinical management
Monitor clozapine levels when smoking changes.
Drug reference
References
Frequently asked questions
Can I take clozapine with smoking cessation (bupropion/varenicline)?
The interaction is rated: Major. Clozapine levels may ↑ when smoking stops (CYP1A2 change).
How serious is the interaction between clozapine and smoking cessation (bupropion/varenicline)?
The interaction is rated: Major. Evidence level: Moderate.
How is the interaction between clozapine and smoking cessation (bupropion/varenicline) managed?
Monitor clozapine levels when smoking changes.
Why do clozapine and smoking cessation (bupropion/varenicline) interact?
↓ PAH induction of CYP1A2.
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